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Medication and Substance Use During Breastfeeding


Ravindu Gunatilake

, MD, Valley Perinatal Services;

Avinash S. Patil

, MD, University of Arizona College of Medicine

Reviewed/Revised Nov 2023

When women who are breastfeeding have to take a medication, they wonder whether they should stop breastfeeding. The answer depends on the following:

  • How much of the medication passes into the milk

  • Whether the medication is absorbed by the baby

  • How the medication affects the baby

  • How much milk the baby consumes, which depends on the baby's age and the amount of other foods and liquids in the baby's diet

Some medications, such as epinephrine, heparin, and insulin, do not pass into breast milk and are thus safe to take. Most medications pass into breast milk but usually in tiny amounts. However, even in tiny amounts, some medications can harm the baby.

Some medications pass into breast milk, but the baby usually absorbs so little of them that they do not affect the baby. Examples are the antibiotics gentamicin, kanamycin, streptomycin, and tetracycline.

When possible, medications should be taken immediately after breastfeeding or before the baby's longest period of sleep.

Medications That Are Relatively Safe During Breastfeeding

Medications that are considered safe include most nonprescription (over-the-counter) medications. Exceptions are antihistamines (commonly contained in cough and cold remedies, allergy medications, motion sickness medications, and sleep aids) and, if taken in large amounts for a long time, aspirin and other salicylates. Acetaminophen and ibuprofen, taken in usual doses, appear to be safe.

Medications that are applied to the skin, eyes, or nose or that are inhaled are usually safe.

Most antihypertensive medications Medications High blood pressure (hypertension) is persistently high pressure in the arteries. Often no cause for high blood pressure can be identified, but sometimes it occurs as a result of an underlying... read more Medications do not cause significant problems in breastfed babies. Women may take beta-blockers during breastfeeding, but the baby should be checked regularly for possible side effects, such as a slow heart rate and low blood pressure.

Caffeine and theophylline do not harm breastfed babies but may make them irritable. The baby's heart and breathing rates may increase.

Even though some medications are reportedly safe for breastfed babies, women who are breastfeeding should consult a health care professional before taking any medication, even an over-the-counter medication, or a medicinal herb. All medication labels should be checked to see whether they contain warnings against use during breastfeeding.

Did You Know...

  • Even though some medications are reportedly safe for breastfed babies, women who are breastfeeding should consult a health care professional before taking any medication, even an over-the-counter medication, or a medicinal herb.

Medications That Require a Doctor’s Supervision During Breastfeeding

Some medications require a doctor’s supervision during their use. Taking them safely while breastfeeding may require the following:

  • Adjusting the dose

  • Limiting the length of time the medication is used

  • Timing when the medication is taken in relation to breastfeeding

Most antianxiety medications Misuse of Antianxiety Medications and Sedatives Antianxiety and sedative medications are prescription drugs used to relieve anxiety and/or help with sleep, but their use can result in dependency and a substance use disorder. Using prescription... read more , antidepressants Medications for depression Depression is a feeling of sadness and/or a decreased interest or pleasure in activities that becomes a disorder when it is intense enough to interfere with functioning. It may follow a recent... read more , and antipsychotic medications Antipsychotic drugs Schizophrenia is a mental disorder characterized by loss of contact with reality (psychosis), hallucinations (usually, hearing voices), firmly held false beliefs (delusions), abnormal thinking... read more require a doctor’s supervision, even though they are unlikely to cause significant problems in the baby. However, these medications stay in the body a long time. During the first few months of life, babies may have difficulty eliminating the medications, and the medications may affect the baby’s nervous system. For example, the antianxiety medication diazepam (a benzodiazepine) causes lethargy, drowsiness, and weight loss in breastfed babies. Babies eliminate phenobarbital (an antiseizure medication and a barbiturate) slowly, so this medication may cause excessive drowsiness. Because of these effects, doctors reduce the dose of benzodiazepines and barbiturates as well as monitor their use by women who are breastfeeding.

Warfarin (a medication that prevents blood from clotting) can be taken if the baby is full-term and healthy. Warfarin does not appear to enter breast milk. People who take warfarin, including women who are breastfeeding, need to have blood tests done periodically to determine whether blood is clotting normally. Warfarin can cause a tendency to bruise or bleed.

Medications and Substances That Should Not Be Taken While Breastfeeding

If women who are breastfeeding must take a drug that may harm the baby, they must stop breastfeeding. But they can resume breastfeeding after they stop taking the drug. While taking the drug, women can maintain their milk supply by pumping breast milk, which is then discarded.

Women who are breastfeeding should consult their health care professional about all the drugs they are taking or about to start.

Women who smoke should not breastfeed within 2 hours of smoking and should never smoke in the presence of their baby whether they are breastfeeding or not. Smoking reduces milk production and interferes with normal weight gain in the baby.

Alcohol consumed in large amounts can make the baby drowsy and cause profuse sweating. The baby's length may not increase normally, and the baby may gain excess weight. Drinking up to 1 standard drink per day does not appear to harm the breastfeeding infant, especially if a woman waits at least 2 hours after a single drink before breastfeeding.

Drugs Mentioned In This Article

Generic Name Select Brand Names
Adrenaclick, Adrenalin, Auvi-Q, Epifrin, EpiPen, Epipen Jr , Primatene Mist, SYMJEPI, Twinject
Hepflush-10 , Hep-Lock, Hep-Lock U/P, Monoject Prefill Advanced Heparin Lock Flush, SASH Normal Saline and Heparin
Afrezza, Exubera
Garamycin, Genoptic, Genoptic SOP, Gentacidin, Gentafair, Gentak , Gentasol, Ocu-Mycin
No brand name available
Emtet-500, Panmycin, Sumycin
Anacin Adult Low Strength, Aspergum, Aspir-Low, Aspirtab , Aspir-Trin , Bayer Advanced Aspirin, Bayer Aspirin, Bayer Aspirin Extra Strength, Bayer Aspirin Plus, Bayer Aspirin Regimen, Bayer Children's Aspirin, Bayer Extra Strength, Bayer Extra Strength Plus, Bayer Genuine Aspirin, Bayer Low Dose Aspirin Regimen, Bayer Womens Aspirin , BeneHealth Aspirin, Bufferin, Bufferin Extra Strength, Bufferin Low Dose, DURLAZA, Easprin , Ecotrin, Ecotrin Low Strength, Genacote, Halfprin, MiniPrin, St. Joseph Adult Low Strength, St. Joseph Aspirin, VAZALORE, Zero Order Release Aspirin, ZORprin
7T Gummy ES, Acephen, Aceta, Actamin, Adult Pain Relief, Anacin Aspirin Free, Aphen, Apra, Children's Acetaminophen, Children's Pain & Fever , Children's Pain Relief, Comtrex Sore Throat Relief, ED-APAP, ElixSure Fever/Pain, Feverall, Genapap, Genebs, Goody's Back & Body Pain, Infantaire, Infants' Acetaminophen, LIQUID PAIN RELIEF, Little Fevers, Little Remedies Infant Fever + Pain Reliever, Mapap, Mapap Arthritis Pain, Mapap Infants, Mapap Junior, M-PAP, Nortemp, Ofirmev, Pain & Fever , Pain and Fever , PAIN RELIEF , PAIN RELIEF Extra Strength, Panadol, PediaCare Children's Fever Reducer/Pain Reliever, PediaCare Children's Smooth Metls Fever Reducer/Pain Reliever, PediaCare Infant's Fever Reducer/Pain Reliever, Pediaphen, PHARBETOL, Plus PHARMA, Q-Pap, Q-Pap Extra Strength, Silapap, Triaminic Fever Reducer and Pain Reliever, Triaminic Infant Fever Reducer and Pain Reliever, Tylenol, Tylenol 8 Hour, Tylenol 8 Hour Arthritis Pain, Tylenol 8 Hour Muscle Aches & Pain, Tylenol Arthritis Pain, Tylenol Children's, Tylenol Children's Pain+Fever, Tylenol CrushableTablet, Tylenol Extra Strength, Tylenol Infants', Tylenol Infants Pain + Fever, Tylenol Junior Strength, Tylenol Pain + Fever, Tylenol Regular Strength, Tylenol Sore Throat, XS No Aspirin, XS Pain Reliever
Advil, Advil Children's, Advil Children's Fever, Advil Infants', Advil Junior Strength, Advil Migraine, Caldolor, Children's Ibuprofen, ElixSure IB, Genpril , Ibren , IBU, Midol, Midol Cramps and Body Aches, Motrin, Motrin Children's, Motrin IB, Motrin Infants', Motrin Junior Strength, Motrin Migraine Pain, PediaCare Children's Pain Reliever/Fever Reducer IB, PediaCare Infants' Pain Reliever/Fever Reducer IB, Samson-8
Cafcit, NoDoz, Stay Awake, Vivarin
Elixophyllin, Quibron T, Quibron T/SR, Respbid, Slo-Bid, Slo-Phyllin, Theo X, Theo-24, Theo-Bid Duracap, TheoCap, Theochron, Theo-Dur, Theo-Dur Sprinkle , Theolair, Theolair SR, Theovent LA, T-Phyl, Uni-Dur, Uniphyl
Diastat, Dizac, Valium, VALTOCO
Luminal, Sezaby
Coumadin, Jantoven
Cequa, Gengraf , Neoral, Restasis, Sandimmune, SangCya, Verkazia, Vevye
Adriamycin, Adriamycin PFS, Adriamycin RDF, Rubex
Jylamvo, Otrexup, Rasuvo, RediTrex, Rheumatrex, Trexall, Xatmep
Eskalith, Eskalith CR, Lithobid
Desyrel, Oleptro
Cycloset, Parlodel
INBRIJA, Larodopa
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